Watch stem bushing



Jan. 6, 1942. c. B. GREENBERG 2,268,749

WATCH STEM BUSHING Filed Feb. 14, 1940 INVENTOR Charles B GrtenbarsATTORNEY Patented Jan. 6, 1942 UNiTED STATES PATENT OFFICE.

WATCH STEM BUSHING Charles B. Greenberg, New York, N. Y. ApplicationFebruary 14, 1940, Serial No. 319,647

4 Claims.

My invention relates to Watches, watch cases, and watch sundries, and inmore detail, to a winding stem bushing capable of gripping and holdingthe watch case halves and thus preventing dust filtration through thestem opening into the watch case and the watch movement.

There are, in use at present, several types of bushings which encase thewatch stem and rest each side of the case. These bushings although madeeither by flaring or by rigidly attaching a flange at each end of atube, cannot actually grip the face of the case except by an accidentalfit. Thus they neither seal the opening about which they rest nor remainfirmly secured in position or prevent dust from entering into the watchand its movements.

It is an object of my invention to so construct my bushing that it willgrasp and hold the halves of the case around and on both sides of thestem opening and thus seal this opening. It is a further object of myinvention to construct a spring motivated bushing in order to providepositive gripping action on the watch case.

In order to accomplish these and other objects, I form my bushing in twoparts with a spring encased therebetween so constructing each part thatan opening is formed between the two parts and the two parts are urgedby the spring toward each other and grip any object held in the openingbetween them.

Further and more specific details and objects of my invention will beshown and described in the accompanying drawing in which Figure 1 is asection through the center of a crown with my invention inserted thereinand holding the halves of a watch case.

Figure 2 is a detail.

Figure 3 is a plan view of the under part of my invention shown inFigure 1 and,

Figure 4 is a vertical section through the center showing a modifiedtype of my bushing.

In the drawing my invention I, illustrated in both Figures 1 and 4 isshown functioning and in position in a crown 2 and resting on, grippingand holding the halves 3 and 4 of a watch case. While the watch casehalves are provided with the customary semicircular stem openings 5 topermit the passage of the stem of the watch movement, the crown 2 is ofthe common type which is provided with the hollowed well part 6, thetube stem winding element I in the center of the well 6 and the circularwell side wall 8.

My invention I as shown in Figure 1 and assembled with the abovedescribed crown and watch case is comprised of a cup shaped element IIhaving a side wall l2 and a bottom I3, the latter part provided with acenter opening I4. Extending through the center opening I4 is a tube I5provided at its lower end with the outward extending flange I6 and atits upper end with the rolled or outward flared tip IT. A coiled springI3 rests between the cup wall and tube on the cups bottom and is held incompression by the washer l9 and is prevented from escaping by theflared tip IT. The cup element II is of a proper size and shape as tofit within the hollowed well part 6 of the crown, while the tube I5 islarge enough to allow the winding element I to extend therein.

Thus the spring acting through the washer I9, the flared tip I1, and thetube I5 continuously forces the face of the flange l6 toward the bottomof the cup l3.

When this bushing is positioned in the crown well the side I2 of the cupelement rest adjacent the side wall of the crown and the stem I of thecrown extends into the tube I5 of the bushing. The bottom I3 of thebushing rests a short dis tance beyond the end of the crown wall and thewatch case halves are gripped in the opening between the bottom I3 andthe flange I6 and held by these two parts. The tube l5 rests in the cutout stem openings 5. By this construction no space is left adjacent thestem openings and there is no chance for dust to enter the case betweenthe stem of the movement and the case opening.

A variation of the flange I6 is shown in Figure 2. The flange I6 iscircular and larger than the stem opening but the flange 20 shown inFigure 2 is lengthened out into an oblong like shape fitting the insideof the case of the watch and so providing a greater bearing area.

The variation of my invention shown in Figure 4 is comprised of a cupshaped element 33 having the side wall 3| and bottom 32. The bottom isprovided with the opening 33. Extending through the opening 33 is thetube element 34 which is provided at its upper end with the flange 35and at its lower end below the bottom 32 with the flared tip orflange-like end 36.

This variation rests in the crown similar to the bushing described shownin Figure 1 but the watch case halves are gripped by the bottom 32 ofthe cup and the flange tip 36. The spring 3'! resting in the cup 30 andheld between the bottom 32 and the flange 35 continuously forces theflanged tip 36 toward the bottom 32 thus gripping and holding the watchcase halves resting therebetween.

As the details described in the drawing show only a few forms of myinvention and since many changes and modifications may be made in thesame invention without changing or departing from the spirit and scopeof the basic idea, I desire to cover all modifications, forms andembodiments coming within the language of any one or more of theappended claims.

I claim:

1. A bushing for a watch case comprising a cup-shaped element having abottom and a side wall and an opening in said bottom, a tube shapedelement having a flange at one end and an enlarged portion at the otherend, said tube extending in the opening in the bottom and the flangeresting below the bottom and the enlarged portion inside the cup, aspring resting in the cup between the cup wall and the tube, and awasher in the cup and about the tube and below and held by the enlargedportion of the tube, the spring acting against the bottom andrespectively through the washer, the enlarged portion of the tube andthe tube, against the flange to force the bottom and flange toward eachother.

2. A sleeve for a watch case and watch movement comprising a cup shapedelement having a side wall and a bottom and said bottom having anopening therein, a tub element extending through the opening in thebottom having at one end a flange and at the other end below the bottoma flared flange-like enlarged section, and a spring within the side wallof th cup and about the tube and resting on the bottom and exertingpressure between the bottom of the cup and the flange of the tube toforce the flange-like enlarged end toward the bottom of the cup.

3. A sleeve for use with a crown and a watch case comprising a cupshaped element having a side wall and a bottom, the bottom having anopening therein, a tube element extending in the opening in the bottomand having a flange at the end of the tube below the bottom and a flaredtip at the end extending in the cup, a spring within the cup, and awasher resting on the spring and held thereagainst by the flared tip ofthe tube, the flange of the tube being oblong shaped in order to permitincreased bearing against the watch case.

4. A bushing for a watch case and watch movement comprising a coiledspring, a first tube having two outward extending flanges and a secondtube concentrically positioned about said first tube and having aninward extending flange located between the flanges of the first tube,and the said spring positioned between the tubes and between the inwardextending and one of the outward extending flanges and functioning tocause compressive pressure between the other of the two flanges and theinward extending flange.

CHARLES B. GREENBERG.

